In turn have the latest on Whitney Houston investigators are zeroing in on our medical records demanding them from doctors all across the country. ABC's Jim -- is on the case in Los Angeles good morning Jim. Good morning George in the corners offices told ABC news that while they're questioning Whitney Houston's doctors. They are cooperating and in fact. Those of subpoenas being issued are mere technicalities a formality to allow the doctors to turn over her medical records. This is Whitney Houston's official death certificate the cause deferred the matter pending investigation. ABC news has learned in LA county coroner investigators have contacted doctors from Los Angeles to Atlanta. It has so far found no evidence of criminal activity. Or any reason to believe Whitney Houston was doctor shopping to abuse prescription drugs. Former LA county coroner investigator Scott carrier says this is a routine inquiry. Done because Houston was only 48 years old and showed no evidence of trauma. And they -- only trying to find out why she does not launch a criminal investigation. The coroner's office is responsible for not who did it but what happened and how was -- That's their responsibility. Their medical detectives. They're not out to apprehend -- suspect prosecute. The coroner's office says everyone is cooperate and this investigation is quote nothing like Jackson. It took the quarters office three months to announce the cause of Michael Jackson's death. His bedroom was filled -- dozens of pill bottles and hundreds of individual pills. Sources tell ABC news. Unlike that case they were just a few pill bottles and Whitney -- week when she died Whitney Houston is scheduled to be eulogize and an invitation only service better childhood church in Newark, New Jersey on Saturday. But it will be live streamed on the Internet. And -- of those tabloid reports that the family does not want Whitney Houston's former husband Bobby Brown to attend the funeral. ABC news is told that while there is bad blood between the families he will be invited because he's the father -- Whitney Houston's trial George. Hey thanks -- me in your -- you you -- you show -- the corners are being very forceful -- -- this case is nothing like Michael Jackson's at all I'm saying there's no evidence. Doctor shopping how can -- be so sure. But what they're seeing is that the couple different things. The first mother were not a load. Pills in her in her -- when they found found her body. That's different than the Michael Jackson case. Also they didn't find a lot of doctors' names on on different bottles of pills. And they also didn't find one doctor so far there was describing a massive amount for the same kind of pill. So they say that -- that -- there's no evidence of that kind of doctor shopping we saw on the Michael Jackson. Lot of different pieces that it's -- Cape Canaveral thanks very much we have much more -- special edition -- 21 moment in time the light the Whitney Houston. That's right 9 -- central on NBC.

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